Women who are exposed to hairspray in the workplace during pregnancy have more than double the risk of having a son with the genital birth defect hypospadias, according to a new study published today in the journal Environmental Health Perspectives.

The study is the first to show a significant link between hairspray and hypospadias, one of the most common birth defects of the male genitalia, where the urinary opening is displaced to the underside of the penis. The causes of the condition are poorly understood.

Previous smaller studies had suggested that hypospadias might be linked to vegetarianism but the new study did not show any increased risk in women who had a vegetarian diet during pregnancy.

Women have a two to three-fold increased risk of having a son with hypospadias if they are exposed to hairspray in the workplace in their first trimester of pregnancy, according to the new study, by researchers from Imperial College London, University College Cork and the Centre for Research in Environmental Epidemiology in Barcelona.

The study suggests that hairspray and hypospadias may be linked because of chemicals in hairspray known as phthalates. Previous studies have proposed that phthalates may disrupt the hormonal systems in the body and affect reproductive development.

In Europe, certain phthalates have been banned from hairsprays and other cosmetic products since January 2005. The women who took part in the study detailed below gave birth in 1997 and 1998 and they were interviewed between 2000 and 2003.

It is thought that hypospadias affects around 1 in 250 boys in the UK and in the USA, although estimates about prevalence vary. Usually, hypospadias can be successfully treated with corrective surgery after a boy reaches his first birthday, but more severe cases can lead to problems with urinating, sexual relations and fertility.

The new research also reveals that taking folic acid supplements in the first three months of pregnancy is associated with a 36 percent reduced risk of bearing a child with the condition. The UK Department of Health already recommends that folic acid supplements are taken up until the twelfth week of pregnancy in order to prevent neural tube defects such as spina bifida.

Professor Paul Elliott, the corresponding author of the research from the Department of Epidemiology and Public Health at Imperial College London, said: "Hypospadias is a condition that, if left untreated, can cause problems in later life. Although surgery to correct it is usually successful, any surgery will be traumatic for the child and his parents. It is encouraging that our study showed that taking folic acid supplements in pregnancy may reduce the risk of a child being born with the condition. Further research is needed to understand better why women exposed to hairspray at work in the first 3 months of pregnancy may have increased risk of giving birth to a boy with hypospadias."

The researchers reached their conclusions after conducting detailed telephone interviews with 471 mothers whose sons had been referred to surgeons for hypospadias and 490 controls, across 120 London Boroughs and Local Authority Districts.

The questionnaires explored a range of aspects of the women's health and lifestyle, including the mother's occupation and possible exposure to different chemical substances, family history of disease, maternal occupation, vegetarianism, smoking and use of folate supplements.

Comments

While this study of women and boys in the United Kingdom, which found a correlation between hairspray exposure and lack of folic acid supplementation, is interesting, it does not explain the increase in hypospadias in the United States.
According to a Centers for Disease Control press release earlier this year, nearly one in 100 boys in the United States is born with hypospadias. Particularly troubling is the increase in severe cases. Market research shows that hairspray sales have declined substantially over the last several years and a nationwide program ordered by the Food and Drug Administration in 1996, in which all grains and cereals must be supplemented with folic acid, has been a measurable success. If hairspray and lack of folic acid were to blame, this male birth defect would have been much more common in the '50s and '60s, when "helmet" hairstyles held in place by hairspray were all the rage and folic acid supplementation was decades away from being realized.

'Hairspray' is much different today than in the 1960s. When we think of hairspray prior to the 1980s, we think of those clouds of spray but those cans used chlorofluorocarbons (CFCs) as a propellant. Almost all aerosol cans today use liquefied petroleum gas - so draw from that what you want. Some hairsprays are also not aerosol at all.

The issue seems to be phthalates and they have been vaguely phased in Europe (in some toys a kid might put in their mouth) and will start to be banned here in some products next year (Bush signed it in August.) Obviously less phthalates in toys for a kid already born with a birth defect is fine, but not helping have less birth defects. The downside to blanket bans with unclear data is you get into the 'DDT problem', where you assume you are correcting a small problem and end up causing a much bigger one trying to replace it. Phthalates have become a lot more common since the 1960s, unlike hairspray.

Hank Cambell makes an excellent point that removing phthalates from children's toys will do nothing to help children with birth defects. While not discounting the role that phthalates may play in exposing children to dangerous chemicals, it would seem beneficial to focus more attention on what could be causing birth defects to occur during gestation. Almost entirely overlooked is the role that prenatal ultrasound may play in causing birth defects. While safety studies conducted on data collected prior to the early '90s was consistently faulted for small sample size, insufficient control populations or exposure after the period of organogenisis, even more disturbing is the lack of any studies since that time.

Many changes in prenatal ultrasound have occurred since then, including an eight-fold increase in allowable acoustic power, a major increase in both prenatal ultrasound applications and the gestational times of exposure, the use of color contrast agents and Doppler ultrasound, etc. While ultrasound is almost universally considered safe and non-invasive, early studies to not support that belief. Ultrasound has several bioeffects which have caused birth defects in animal studies. Given those fact, due diligence calls for a complete review of the role that prenatal ultrasound may play in emerging birth defects and disorders. For more information, readers are invited to read my article on the link between prenatal ultrasound and autism at: http://midwiferytoday.com/articles/ultrasoundrodgers.asp or read my science blog at http://carolinerodgers.wordpress.com

Fathers exposed to similar toxic substances could also be a cause. An ex-boyfriend who had Hypospadias had a father who owned a gas and fuel oil delivery service which exposed him (the father) to fuel oil six days a week.